[vortex] 3c905C: Packet losses, but only with a switch (2nd , part)

[Bogdan Costescu]

On Tue, 4 Jul 2000, Giuseppe Ciaccio wrote:

> > How do you observe the packet loss? And how many packets are lost?
> I use "ping -f".  My machines are fast enough to absorb it.

I haven't read the source of ping, but my understanding is that '-f'
counts ECHO_REQUEST vs. ECHO_REPLY which might not be so precise. Have you
tried to look at the packet counters (given by ifconfig for example) ? Of
course, that means that you need to do it with some network services
disabled. Another posibility is to compare the Linux packet counters with
the switch internal counters (provided that you can read them); the switch
might also give you some info about errors.

> With crossover cable as well as repeater hub, mii-diag reports:
>
> Basic registers of MII PHY #0:  0000 0000 0000 0000 0000 0000 0000 0000.
>  Basic mode control register 0x0000: Auto-negotiation disabled, with
>  Speed fixed at 10 mbps, half-duplex.
>  Basic mode status register 0x0000 ... 0000.
>    Link status: not established.
>  Link partner information information is not exchanged
> when in fixed speed mode.

Ouch! This is bad. Basic registers are all zero; I'm surprised that it
works at all! Can you provide a more detailed mii-diag output ? (and the
driver init message which identifies the card and mode in which is working
as per Donald's request).
Do you obtain this kind of output only when you enable autonegotiation?

> Both NICs were autonegotiating.

Well... I'm not so sure about this! You might try to force them to
autonegotiate using module option '8'. As far as I can see from the driver
source, the module options have priority over card "defaults" (EEPROM
values).

Sincerely,

Bogdan Costescu

IWR - Interdisziplinaeres Zentrum fuer Wissenschaftliches Rechnen
Universitaet Heidelberg, INF 368, D-69120 Heidelberg, GERMANY
Telephone: +49 6221 54 8869, Telefax: +49 6221 54 8868
E-mail: Bogdan.Costescu@IWR.Uni-Heidelberg.De